Shop Floor Talk  

Go Back   Shop Floor Talk > Welding and Metalworking Forums > Fabrication

SFT Search:   
Reply
 
Thread Tools Display Modes
  #1  
Old 07-22-2019, 02:19 PM
Scratch Scratch is offline
Senior Member
 
Join Date: Feb 2007
Location: Hudson WI
Posts: 526
Default DIY Magnetic Chucks

Yesterday, I heard a little about using microwave transformers to make a DIY magnetic chuck for grinding small parts so I did a little bit of research. I also removed the 3 transformers from my junk microwaves.
I was happy at how easy they were to remove from all 3 microwaves first of all. I just removed the main cover and the transformer bolts were all easy to access. No need to dig into the deep depths of the microwaves.

But I was super happy at how easy they were to turn into electromagnets! The only hard part was removing the primary winding, and that wasn't too bad either! I even got them to work great using one AA battery! I put one battery on it then stuck a small piece of metal to the magnet. Then I used a flap disc grinder and a wire wheel grinder on it, pushing real hard, and the piece never moved. And that was with one AA battery! I also had a double battery bucket and hooked that up and it worked even better.

Then I hooked it up to my 18V drill battery and was shocked at the pull it had! Way more than I needed but still super cool!

My question is has anyone gotten these to work as small part holders and how did you power them?
Convert AC to DC with some extra electronics?
Just use Drill batteries?
Use 12V alarm batteries?
Stick with a couple toy batteries?

What about wiring? My AA setup wiring never got warm, but my 18V battery made my wires start to get warm and I'm not sure the best way to go about keeping them from getting too hot.

Any input?

Here's some pics, and if you want my advice... PULL THAT TRANSFORMER BEFORE YOU TOSS THAT MICROWAVE!
Attached Thumbnails
Click image for larger version

Name:	1.jpg
Views:	177
Size:	145.1 KB
ID:	151584   Click image for larger version

Name:	3.jpg
Views:	169
Size:	134.7 KB
ID:	151585  
Reply With Quote
  #2  
Old 07-22-2019, 02:39 PM
astronut's Avatar
astronut astronut is offline
Senior Member
 
Join Date: Jun 2019
Location: Down South
Posts: 600
Default

My magnets that I have pulled from microwave oven reactors. Self powered and no external power needed to make them work. I have pulled many from failed microwave ovens for myself and other owners and provided them with very strong magnets.
Attached Thumbnails
Click image for larger version

Name:	000_2456.jpg
Views:	97
Size:	189.0 KB
ID:	151586  
__________________
I love the smell of napalm in the morning. It smells like, victory!

Victor Torch Set With Meco Regs
Lincoln Weld Pak 100
Giant Tech Arc 200
Miller Roughneck2E
Reply With Quote
  #3  
Old 07-22-2019, 03:40 PM
cutter's Avatar
cutter cutter is online now
Curmudgeon
 
Join Date: Jun 2004
Location: Lubbock,Texas
Posts: 33,001
Default

Quote:
Originally Posted by Scratch View Post

But I was super happy at how easy they were to turn into electromagnets! The only hard part was removing the primary winding, and that wasn't too bad either!
Why didn't you just leave the primary windings?
__________________
cutter
Housekeeping Staff: the Gatekeeper
Director of Policy, Syntax and Grammar (by appointment)

"Dr. Chandran, will I dream?"

Just Keep Walking

"I am not a body, I am free.
For I am still as God created me."
Reply With Quote
  #4  
Old 07-22-2019, 09:52 PM
JBFab JBFab is offline
Elite Member
 
Join Date: Oct 2006
Location: NorthCentral Wisconsin
Posts: 1,256
Default

If you do end up using power tool batteries, I saw these available for DeWalt 20v batteries. If you rig up your own the two outside pi s are + and - while the inner pins allow you to select lower voltages by only engaging certain series of cells - full disclaimer, I don't know how that would affect battery life.Click image for larger version

Name:	Screenshot_20190722-214919_Amazon%20Shopping.jpeg
Views:	89
Size:	57.3 KB
ID:	151600

Sent from my mobile device using ShopFloorTalk mobile app
__________________
I believe the appropriate metaphor here involves a river of excrement and a Native American water vessel without any means of propulsion.
Reply With Quote
  #5  
Old 07-22-2019, 09:52 PM
Lew Hartswick Lew Hartswick is offline
Elite Member
 
Join Date: May 2008
Location: Albuquerque NM
Posts: 3,749
Default

I think it was the secondary he removed. ( The high voltage for the maggie. I don't see any sign of the filament [pardon me Heater] winding either.) :-)
...lew... and old Radar maintenance S/Sgt. :-)
Reply With Quote
  #6  
Old 07-22-2019, 11:36 PM
Dave Lee's Avatar
Dave Lee Dave Lee is offline
Armchair Webbie
 
Join Date: Jan 2007
Location: near Philadelphia, PA.
Posts: 3,634
Default

Quote:
Originally Posted by astronut View Post
My magnets that I have pulled from microwave oven reactors. Self powered and no external power needed to make them work. I have pulled many from failed microwave ovens for myself and other owners and provided them with very strong magnets.
Not to hijack this thread but, if you look on the youtube channel by poroldchap, he shows how to take those magnets and make one capable of lifting a small anvil. Also, I saw someone use a similar magnet as a demagnetizer by passing a screwdriver in and out of the hole. Without touching the sides, of course.


Dave
__________________
Hoocha Momma!, who chop-id-da cheese?
Reply With Quote
  #7  
Old 07-23-2019, 09:48 PM
Scratch Scratch is offline
Senior Member
 
Join Date: Feb 2007
Location: Hudson WI
Posts: 526
Default

Quote:
Originally Posted by cutter View Post
Why didn't you just leave the primary windings?
I guess you want the primary winding at the bottom of the base. The secondary winding is there. You need to pull the primary, then the secondary, then put the primary where the secondary was to get the most effect.
Reply With Quote
  #8  
Old 07-25-2019, 05:27 PM
digr's Avatar
digr digr is offline
The Real Deal
 
Join Date: Apr 2005
Location: Duluth MN
Posts: 8,231
Default

I would use mags from a electric brake system
__________________
Drawing by Smartdraw
Reply With Quote
  #9  
Old 07-27-2019, 09:59 AM
GWIZ's Avatar
GWIZ GWIZ is offline
SFT Historian
 
Join Date: Feb 2006
Location: USA
Posts: 6,898
Default

Quote:
Originally Posted by Scratch View Post

What about wiring? My AA setup wiring never got warm, but my 18V battery made my wires start to get warm and I'm not sure the best way to go about keeping them from getting too hot.

Any input?

Here's some pics, and if you want my advice... PULL THAT TRANSFORMER BEFORE YOU TOSS THAT MICROWAVE!
You need an amp meter to figure out how much power you need, if you do not know how to connect one search the net and find out.
batteries may not last that long and let the part go.

Ideally you may want both on a power failure.
__________________
*
*
The factory of the future will have only two employees, a man and a dog. The man will be there to feed the dog. The dog will be there to keep the man from touching the equipment. ~Warren G. Bennis
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Web Search:

All times are GMT -5. The time now is 06:14 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.